The statements in this section merely provide background information related to the present disclosure and do not constitute prior art.
Recently, in college entrance examinations and domestic large corporations, grade-oriented evaluation is changing to evaluate actual English proficiency in speaking/writing. In an English ability test, a writing evaluation system is being also introduced to evaluate a writing ability.
The inventor(s) has noted that an existing writing evaluation system grammatically analyzes an already-written sentence and evaluates whether or not the written sentence is grammatically correct through error detection. At this time, the process of analyzing the written sentence involves analyzing morphemes of the sentence and tagging the morphemes with parts of speech. The inventor(s), however, has noted that an existing morpheme analyzing and part-of-speech tagging device depends upon only part-of-speech sequence information without considering vocabulary, parts of speech, meanings, and contextual co-occurrence relations of surrounding words. The inventor(s) has experienced that the accuracy of the device is significantly degraded.
The inventor(s) has noted that to improve the accuracy of the device, an error detection method of complementarily applying rule information and statistical information of vocabulary using a dictionary, a language model, etc. in which peripheral language rules and word context information are constructed.
The inventor(s) has noted that the language model in particular represents a connection relationship between words based on statistical grammatical information using a probability. The language model can be easily extracted from many text sentences of a given field and has high accuracy in error detection. The inventor(s), however, has noted that actual language varies with time and place rather than being standardized rules, and thus often differs from the statistical grammatical information. For example, implied words, Internet terminology, newly established modern words, etc. violate grammar, but is frequently used in real life. In this regard, the inventor(s) has experienced that there is a need of a scheme for accurately detecting grammatical errors based on statistical grammatical information.